This invention relates generally to seed planting apparatus, and more particularly to a controlled planting system which automatically controls and maintains a preselected density of population of seeds delivered to furrows formed in a field and maintains a spatial relationship between seeds in various seeding configurations.
Present day farming techniques include, among other things, the automatic planting and harvesting of crops. The planting of seeds to establish a crop field is often accomplished by driving a tractor, or other suitable vehicle, while pulling a seed dispensing device, preferably several such devices extending transversely of the direction of travel of the tractor, while seeds are continuously dispensed into a corresponding number of furrows formed in the field. This automatic seed dispensing apparatus is generally driven by a drive wheel which is part of the planter. In such prior art regarding automatic seed dispensing devices, the rate at which seeds are dispensed can be altered by manually setting the drive coupled to the seed dispenser.
In order to obtain the maximum yield per acre, a farmer must accurately control the number of seeds planted per acre. To accomplish this in the past, the farmer would incorporate a counter device at the seed dispenser of the planter and count the number of seeds being dispensed. During this period of counting, the farmer would either manually or automatically incorporate means to calculate the distance travelled so he could determine the area covered. After travelling a predetermined distance during which time seeds are planted, the farmer can then calculate the density of population of seeds for the small area. If the density of population is in accordance with his prescribed yield for that particular field, the farmer may continue his planting operation without change. However, if adjustment is to be made to the planting equipment the farmer must make it at this time and take a second sampling of the number of seeds dispensed during travel over another prescribed area. While being somewhat of an automatic system for the planting of seeds this arrangement has the disadvantage in requiring substantial amounts of time for setup and checking before continuous planting operation can commence. Furthermore, the accuracy of the population density of the seeds planted in this manner is at best only a close approximation because of the possibility of very closely spaced seeds being dispensed in a manner to produce coincident seed count pulses which would register as a single seed count.
With reference to U.S. Pat. No. 7,726,251, the above described inventive concepts differ significantly from that taught in this patent. In particular, the '251 patent appears to operate in the time realm in performing its comparisons. It mentions that row dispensers could be displaced for-aft locations but does not explain how this is to be handled using the time based comparison method. With respect to EP 1,415,523 there is disclosed a seed drill oriented seed planting system that appears to use an external positioning system to deposit seeds in a furrow. In practice, this approach fails to take into account the speed of the tractor which can increase or decrease seed spacing even though you may know where you want to release the seed but would not know the final location of the deposited.
The aforementioned planting systems and ability to keep track of the seeds planted in a field are further complicated where the farmer intends to increase the density of seeds to be planted per acre and the conditions of the terrain can change. Also, the adjustment of the planter to control the spatial relationship between two adjacent (or twin rows) planting units adds an additional complication.